Efficient intra prediction mode decision for H.264 video

In this paper, we propose an efficient 4×4 intra prediction mode decision method for the complexity reduction of H.264 video coding. Based on the observation that a good prediction could be achieved when local edge direction of a block is in the same direction as the intra prediction mode, local edge direction of block is obtained in transform domain to filter out majority of intra prediction modes. By filtering out majority of intra prediction modes, we only have to consider a candidate set of most highly probable 4×4 intra prediction modes for which the rate distortion optimization process should be performed. Experimental results show that the proposed method can achieve a considerable reduction of computation while maintaining similar PSNR and bit rate.